The Blood and Tissue Core provides an essential resource for local and collaborative research. The Core is designed to exist as a core without walls. The primary responsibility ofthe Core is to ensure the quality of processing and storage of human specimens. We work closely with the Massachusetts General Hospital's NIH-funded Chnical Research Center (CRC) which is part of the Harvard Clinical and Translational Science Center (CTSC), and we have established collaboration with Dr. James Liao's laboratory at the BWH. We propose a Blood and Tissue Core responsive to the aims set forth in the Specialized Program of Translational Research in Acute Stroke program announcement (PAR-09-254), which will support ARISE (project #2) at MGH and Neu-START at BWH, and collect and share plasma and DNA samples within the SPOTRIAS network. The aims ofthe Partners SPOTRIAS Blood and Tissue Core are: 1. To process, maintain, and distribute blood specimens collected in ARISE (Project #2) at MGH. 2. To support blood collection and processing for the Neu-START study at the BWH. 3. To store blood specimens collected on SPOTRIAS subjects for future collaborative studies. 4. To collect genetic material for submission to the NINDS repository for use in future genetic studies proposed within Partners, the SPOTRIAS network, the International Stroke Genetics Consortium (ISGC), and the broader scientific community.